I wanna go here next time I’m in LA.
http://www.mjt.org/
Sadly, my mother is at San Fernando Mission Cemetery. And she isn’t working there.
But it’s been a few years. So, either 
or 
is OK.
The Huntington Gardens in San Marino is nice, although you’d want to have a car to get there. I’d second the Getty Museum, too. I think it’s free if you can get there by public transportation (although that’s kind of far from LAX). If you drive, you have to make a parking reservation in advance. You could always go to Disneyland, although on your schedule, that would be kind of insane - it’s a pretty long haul from the airport.